Pulsation impact spray nozzle

ABSTRACT

A nozzle for producing an impacting pulsating spray of liquid comprises a hollow elongate tube having an inner chamber and a pair of spaced inlet and outlet plugs fitted one in each opposite end of the tube thereby to define the chamber. The outlet plug has an axial funnel-shaped duct defined therethrough with the flare of the duct open to the exterior of the nozzle. The inlet plug has a duct defined therethrough with its mean crosssectional area substantially less than the mean cross-sectional area of the chamber. Liquid is fed into the chamber through the inlet plug and emerges out of the nozzle through the outlet plug as a randomly pulsating conical spray having a high impacting force.

United States Patent Hruby, Jr.

[451 Aug. 15, 1972 [54] PULSATION IMPACT SPRAY NOZZLE [72] Inventor: John 0. llruby, .Ir., Burbank, Calif.

[73] Assignee: Rain Jet Corp., Burbank, Calif.

[22] Filed: July 27, 1970 [211 Appl. No.: 58,361

[52] US. Cl ..239/101, 239/590, 239/DlG. 16

[51] Int. Cl. ..B05b l/08 [58] Field of Search ..239/101, 589, 590, 596, 598, 239/600, 601, 468, 471, DlG. 16

[56] Reierenees Cited UNITED STATES PATENTS 53,109 3/1966 Burcharclt .....239/596 2,432,651 12/1947 Bimpson "239/589 X 1,719,045 7/1929 Carter .'....239/590 X 3,082,961 3/ 1963 l-lruby, .lr.... ....239/598 3,341,133 9/1967 l-lruby et al. ....239/598 964,445 7/1910 Muller ..239/468 985,522 2/1911 Gibbs ..239/468 X 2,536,832 1/1951 Altorfer ..239/468 Breting ..239/468 X Wahlin ..239/468 Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-John J. Love Attorney-Christie, Parker & Hale [57] ABSTRACT A nozzle for producing an impacting pulsating spray of liquid comprises a hollow elongate tube having an inner chamber and a pair of spaced inlet and outlet plugs fitted one in each opposite end of the tube thereby to define the chamber. The outlet plug has an axial funnel-shaped duct defined therethrough with the flare of the duct open to the exterior of the nozzle.

- The inlet plug has a duct defined therethrough with its mean cross-sectional area substantially less than the mean cross-sectional area of the chamber. Liquid is fed into the chamber through the inlet plug and emerges out of the nozzle through the outlet plug as a randomly pulsating conical spray having a high impacting force.

8 Claims, 9 Drasving Figures PULSATION IMPACT SPRAY NOZZLE BACKGROUND OF THE INVENTION 1 Field of the Invention This invention relates to liquid spray nozzles and, more specifically, to nozzles which emit a pulsating spray having a substantial impacting force with each pulse.

2. Description of the Prior Art Liquid spray nozzles, useful for a multitude of purposes, are known. For instance, liquid spray nozzles have been designed to emit a steady stream of fluid having an impacting force dependent solely upon the pressure of the liquid supplied to the nozzle. Additionally, spray nozzles have been designed to emit a steady conical spray pattern composed of discrete droplets of liquid. A common use of a steady stream spray nozzle is in, fire fighting and the like; nozzles producing conical and similarly shaped discrete droplet spray patterns are commonly used for watering plants and the like, and also in overhead automatic fire sprinkler systems.

Spray nozzles have also been employed to project a liquid stream onto surfaces containing sedimentary deposits in order to remove such deposits from the surface. For example, the ordinary household driveway becomes laden with sand and dirt and other sedimentary deposits. In the past, the steady solid or conical stream spray nozzles have been used to remove the sedimentary deposits from such surfaces. These types of spray nozzles, however, are not highly efficient in sedimentary deposit removal for two reasons: 1) If a steady stream spray is used, the spray will impact the surface with a substantial force but only over a small and confined area. 2) When a conical-shaped spray of discrete droplets is'used, a wide area of the surface will be hit by the spray, but the force of impact will be minimal. In either case, it is a time-consuming chore to remove sedimentary deposits from driveway and pavement surfaces and the like with the aforementioned spray nozzles; such nozzles also require the use of substantial quantities of water to effectively clean a driveway.

It is desirable, therefore, to be able to quickly and efficiently remove sedimentary deposits from pavement surfaces and the like by the traditional means of emitting a liquid spray from a suitable nozzle. Desirably, however, the spray should be designed to impact the .greatest possible area with the greatest amount of force, and to use water efliciently for such purpose.

SUMMARY OF THE INVENTION The nozzle according to the present invention emits a forcefully impacting pulsating spray. The emitted spray is conical-shaped to cover a wide surface area. The pulsation of the spray has the effect of increasing the force of impact in direct relation to the time differential-between pulses. In other words, each pulse of liquid discharged from the nozzle not only covers a great amount of area on the surface, but also hits the surface with a substantial impacting force to, in effect, hammer deposits from the surface to which the discharge is directed. The present nozzle results in efficient usage of liquid.

Generally speaking, the present nozzle comprises a hollow elongate tube having an elongate inner chamber with inlet and outlet ends. An outlet plug is contained within the tube and closes the chamber at the outlet end thereof. The outlet plug has a duct defined therethrough, such duct being of funnel-like configuration with a conical flare open to the exterior of the nozzle. An inlet plug is contained within the tube and closes the inlet end of the chamber. The inlet plug has a duct defined therethrough, the mean cross-sectional area of which is substantially less than the mean transverse cross-sectional area of the chamber. The tube, adjacent to the inlet end of the chamber, is adapted to be connected to a source of liquid under pressure.

This unique configuration of ducts in plugs situate at either end of a hollow elongate tube causes a steady stream of fluid entering the tube to be emitted as a conical-shaped pulsating spray having a high degree of impacting force.

BRIEF DESCRIPTION OF THE DRAWING These and other aspects and advantages of the present nozzle are more fully described with reference to the drawing in which:

FIG. 1 is a cross-sectional elevation view of a presently preferred embodiment of the invention;

FIG. 2 is a view taken along lines 22 in FIG. 1;

FIG. 3 is a view taken along lines 3-3 in FIG. 1;

FIG. 4 is a front elevation view of another inlet plug useful in a nozzle according to this invention;

FIG. 5 is a rear elevation view of the inlet plug shown in FIG. 4;

FIG. 6 is a partial cross-sectional view of another inlet plug useful in a nozzle according to this invention;

FIG. 7 is a front elevation view of yet another alternative inlet plug;

FIG. 8 is a front elevation view of yet another inlet plug useful in a nozzle according to this invention; and

FIG. 9 is a view taken along line 9-9 in FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT A pulsation impact spray nozzle 1 has a body defined by a hollow elongate tube 10 having an inner chamber 11, an open inlet end 12, and an outlet end 14. The tube and the entire nozzle is preferably made of brass or high impact plastic such as Lexan, but may be fabricated of other materials if desired.

An outlet plug 16 is disposed within tube 10 at its outlet end. Preferably the outer end of the plug is in the same plane as the outlet end 14 of the tube and has its peripheral extent engaged with the inner walls 17 of the tube sufficiently tightly that no liquid can pass between the plug and the tube. Plug 16 defines a funnel-shaped duct 18 axially therethrough with a mean cross-sectional area substantially less than the mean cross-sectional area of chamber 11 transverse of tube 10. Duct 18 has a conically flared portion 20 which opens to the exterior of the nozzle. The remainder of the duct is composed of a right circularly cylindrical aperture 22 which completes a fluid channel through plug 16 into chamber 11 situate between plug 16 and an inlet plug 24. The length of chamber 11 between plugs 16 and 24 is substantially greater than the mean transverse dimension of chamber 1 1 between plugs 16 and 24.

Inlet plug 24 is contained within tube 10 at its open inlet end 12 and has its peripheral extent tightly engaged with inner walls 17 of the tube. The outer end of plug 24 may lie in the same plane as the open inlet end 12 of the tube 10, as shown, or the inlet plug may be displaced a short distance along the tube from its inlet end if desired. Plug 24, spaced from plug 16 along the tube by the length of chamber 11 and fabricated of preferably brass or Lexan material, contains an inlet duct 26 defined therethrough. The cross-sectional area of inlet duct 26 is less than that of outlet duct 18. The longitudinal axis 28 of duct 26 is inclined or oblique, i.e., disposed at an angle, to the longitudinal axis 30 of tube '10. Additionally, duct 26 is disposed with its axis 28, in one end 32 thereof, spaced from longitudinal axis 30 so that duct 26 is eccentric to the axis of tube 30. Since duct 28 is both inclined out of parallel to tube axis 30 and is eccentric to the tube axis, duct 28 has its length arranged skew to the length of tube 10 and chamber 1 1.

As shown in FIGS. 2-10, numerous configurations for duct 26 may be used consistent with the teachings of the. present invention. The main criteria for all of the I configurations, in order to insure a pulsating discharge from tube 1, is that the mean cross-sectional area of duct 26 be substantially less than the mean cross-sectional area of chamber 1 1. As shown in FIGS. 2 and 3, inlet duct 26 is of rectangular cross-sectional configuration. The mean cross-sectional area of duct 26 is substantially less than that of chamber 1 1.

Consistent with insuring that the mean cross-sectional area of inlet duct 26 be substantially less than that of chamber 11, the area of the inlet duct is chosen as large as possible in order to reduce back pressure and raise the amount of volume discharge rate of the nozzle. Thus, the other duct configurations for plug 24, shown in FIGS. 4-10, all provide as large an inlet duct mean cross-sectional area as possible, but still maintain such area substantially less than that of the chamber. The inlet duct configurations and locations shown in FIGS. 1-10 are not inclusive, but are merely exemplary of numerous possible duct configurations and locations that can be used.

Plug 24a (FIGS. 4 and has a right-circularly cylindrical inlet duct 36 defined therethrough with its longitudinal axis inclined but not eccentric to the longitudinal axis of chamber 11. The axis 38 of duct 36 at plug end 34 is shown concentric with the longitudinal axis 30 of the chamber, whereas the center of duct 36 at plug end 32 is eccentric with axis 30.

It is not necessary for the longitudinal axis of the inlet duct to be skew to tube axis 30. As is shown in FIG. 6, an inlet plug 24b has a cylindrical-shaped duct 40 which is entirely concentric to axis 30 of chamber 11. The main criteria relates to the mean cross-sectional area dimensions of the duct relative to the chamber, as above described.

FIG. 7 shows another inlet plug 24c having a pair of ducts 42 and 44, both of essentially rectangular-shaped cross-section. As before, the total mean cross-sectional area of ducts 40 and 42, although made as large as possible to reduce the back pressure and increase the amount of discharge, is still substantially less than the mean crosssectional area of chamber 1 l. Ducts 42 and 44 are parallel to each other through plug 24c and are parallel to tube axis 30. It is within the scope of the invention, however, that ducts 42 and 44 be disposed out of parallel to each other and to tube axis 30.

FIGS. 8 and 9 show yet another inlet plug 24d having an essentially rectangular-shaped duct 46. As shown in FIG. 9, the duct is defined, in part, by a pair of parallel side walls 48 and 50 which are also parallel to the tube axis 30. The end of side wall 48 closest to plug end 32 is chamfered, as is the end of side wall 50 closest to plug end 34. The chamfers, in effect, convert a duct parallel to axis 30 into a duct skew to the tube axis.

The outer walls of tube 10 are threaded, as at 35, at the inlet end thereof so as to allow the nozzle to be connected to a source of pressurized liquid. Liquid is then fed into the nozzle by passing the liquid through inlet duct 26 (see FIGS. 1-3) into chamber 11. Fromwithin chamber 11, the liquid proceeds toward plug 16 and then through the funnel-shaped duct 18 in such plug. The liquid is emitted from the conical-shaped portion 20 of the duct as a conical-shaped spray which pulsates randomly in frequency and precise direction and has a high degree of impacting force. That is, the direction of heaviest discharge from the nozzle fluctuates randomly within limits defined by the cone 20 of outlet duct 18. Liquid emerged continuously from the nozzle, but the volumetric rate of discharge varies randomly.

' The unique results obtained by the spray nozzle according to the present invention, i.e., an ever-shifting conical-shaped pulsating spray having a high degree of impacting force, are due to the following combination of structural circumstances:

1) the fact that the duct in the outlet plug is funnelshaped with the conical-shaped portion thereof closer the open outlet end of the chamber; 2) the fact that the inlet plug constrains the fluid to pass through a duct having a mean cross-sectional area substantially less than the mean cross-sectional area of the chamber: and 3) the volume of chamber 11 relative to the rate at which liquid is supplied to the chamber through the inlet duct of the nozzle.

The theoretical principle involved in pulsation spray emission can be understood very easily. If liquid flowing into a nozzle is fed in a continuous stream and the nozzle chamber is made to delay the emission of the liquid for a time in order to establish pulses, the result is that the pressure inside the chamber increases during the time in which the liquid is held therein, thereby increasing the force of emission once conditions change to allow a pulse of liquid to be emitted and thereby reduce the pressure in the chamber.

The precise dimensions of the relevant portions of a preferred spray nozzle having the features shown in FIGS. 1, 4 and 5 are as follows: I) Dimension A is the greatest diameter of conical-shaped portion 20 of funnel-shaped duct 18 and has a value of 0.550 inch. 2) Dimension B is the inner diameter of tube 10 and has a value of 0.700 inch. 3) Dimension C is the elongate length of plug 16 and has a value of 2.0 inches. 4) Dimension D represents the smallest diameter of funnel-shaped duct 18 and has a value of 0.25 inch. 5) Dimension E represents the diameter of circular cylindrical duct 26 and has a value of 0.375 inch. 6) Dimension F is the axial length of plug 24 and has a value of 0.25 inch. 7) Dimension G is the axial length of chamber 11 and has a value of 4.75 inches. 8) Angle 0 represents the angle at which duct 26 is inclined to the longitudinal axis of the tube and has a value of 10. 9) Angle 0 represents the angle of conical expansion of portion of duct 18 and has a value of 8.

The above precisely defined dimensions are merely those employed on a particular nozzle according to this invention. These dimensions are not deemed to be exclusive when applied to the invention as a whole, but can be varied and still achieve the desired result. For instance, if dimension G is increased, the time duration between pulses will also be increased, thereby increasing the force of impact. With dimensions of G at 4.75 inches, the pulses are in the form of a pulsating surge superimposed on a continuous flow. Thus, if the value of G is increased, the time interval between surges increases, but between each surge (pulse) liquid is still discharged.

Angle (b may also be changed in order to change the conical configuration of the spray emitted from the nozzle. The angle 0 is neither critical nor essential, as explained above, but should have a value in the range of from 0 to 45 in order to achieve a maximum pulsating efi'ect. As shown in the embodiment of FIGS. l-3, duct 26 not only is inclined to axis 30 within an angular range of from 0 to 45, but is also eccentric to axis 30.

It has been determined empirically that best performance over a wide range of applied liquid pressures is achieved if the inlet duct to chamber 11 is skew (inclined and eccentric) to the chamber axis. From this optimum, the pressure range over which pulsation occurs decreases as the nozzle has the following features: inlet duct inclined but not eccentric to chamber axis, inlet duct eccentric but not parallel to chamber axis, and inlet duct parallel to and coaxial with chamber axis. The inlet duct arrangement shown in FIG. 7 concerning inlet plug 240 is of the parallel-coaxial type since the center of area of ducts 42 and 44 as a combination coincides with the chamber axis.

What has been described therefore is the unique spray nozzle for emitting a pulsating conical-shaped spray having a high degree of impact force.

What is claimed is:

l. A nozzle for producing an impacting pulsating liquid spray comprising a. a body defining an elongate inner chamber having opposite inlet and outlet ends spaced along an axis of the chamber; an outlet duct defined through the chamber outlet end and having a cross-sectional area substantially less than the mean transverse cross-sectional area of the chamber and a length greater than its mean transverse dimension, the outlet duct including an outwardly flared conical-shaped outlet portion open to the exterior of the body; and

c. an inlet duct defined through the inlet end of the chamber and having a mean cross-sectional area substantially less than the mean transverse crosssectional area of the chamber and less than the effective cross-sectional area of the outlet duct, the inlet duct having a longitudinal axis disposed oblique to the axis of the chamber.

2. A nozzle according to claim 1 in which the inlet duct has its axis disposed eccentric to the axis of the h t f th ds f e' td t. c R ii zzl agcor i g to cia tim in i vllich the inlet duct has an essentially rectangular cross-sectional configuration.

4. A nozzle according to claim 1 in which the inlet duct is disposed skew to the axis of the chamber.

5. A nozzle according to claim 1 wherein the outlet duct is aligned coaxially with the chamber.

6. A nozzle according to claim 1 including a second inlet duct defined through the inlet end of the chamber, the total mean cross-sectional area of both inlet ducts being substantially less than the mean transverse crosssectional area of the chamber and less than the effective cross-sectional area of the outlet duct.

7. A nozzle according to claim 1 wherein the chamber has a length between the inlet and outlet ends thereof which is greater than the mean transverse dimension of the chamber.

8. A nozzle according to claim 1 wherein the chamber has a right circularly cylindrical configuration. 

1. A nozzle for producing an impacting pulsating liquid spray comprising a. a body defining an elongate inner chamber having opposite inlet and outlet ends spaced along an axis of the chamber; b. an outlet duct defined through the chamber outlet end and having a cross-sectional area substantially less than the mean transverse cross-sectional area of the chamber and a length greater than its mean transverse dimension, the outlet duct including an outwardly flared conical-shaped outlet portion open to the exterior of the body; and c. an inlet duct defined through the inlet end of the chamber and having a mean cross-sectional area substantially less than the mean transverse cross-sectional area of the chamber and less than the effective cross-sectional area of the outlet duct, the inlet duct having a longitudinal axis disposed oblique to the axis of the chamber.
 2. A nozzle according to claim 1 in which the inlet duct has its axis disposed eccentric to the axis of the chamber at one of the ends of the inlet duct.
 3. A nozzle according to claim 1 in which the inlet duct has an essentially rectangular cross-sectional configuration.
 4. A nozzle according to claim 1 in which the inlet duct is disposed skew to the axis of the chamber.
 5. A nozzle according to claim 1 wherein the outlet duct is aligned coaxially with the chamber.
 6. A nozzle according to claim 1 including a second inlet duct defined through the inlet end of the chamber, the total mean cross-sectional area of both inlet ducts being substantially less than the mean transverse cross-sectional area of the chamber and less than the effective cross-sectional area of the outlet duct.
 7. A nozzle according to claim 1 wherein the chamber has a length between the inlet and outlet ends thereof which is greater than the mean transverse dimension of the chamber.
 8. A nozzle according to claim 1 wherein the chamber has a right circularly cylindrical configuration. 